Reading Text Messages and Emails: Fair or Foul?

We all remember what it was like to be a teenager. We needed money, rides to the movies and depended on our parents for pretty much every facet of our existence, but what we wanted, or needed, most was privacy.

We didn't want our parents going through our stuff and anything incriminating found in the course of what we felt an illegal search and seizure was considered inadmissible in the court of teenage logic.

Most parents and kids would likely agree that searching drawers and reading diaries or journals constitutes an overstepping of parental bounds. I always felt that only that which was out in the open was fair game; anything that was hidden, however poorly, was private.

But how far can parents go when investigating suspicious activity? Is it OK for parents to read text messages or emails? Most parents pay for their kid's cell phone, so does that give Mom and Dad the right to know exactly how their kids are using them?

Can parents check their kid's Facebook pages or Twitter feeds if they're not public? What about reading emails? And if so, when is it appropriate to do so? Do parents always have the right to know what they're kids are up to or only when they feel their children are in imminent danger?

So, what do you think: to what extent can parents search their kid's "private" correspondences? And when, if ever, is it OK for parents do so?